Selective interaction of rare-earth centers perturbed by intrinsic defects in lanthanum hexagonal aluminate doped with cerium and terbium

The spectral luminescent properties of lanthanum-magnesium hexaaluminate (LMHA) LaMgAl11O19 activated with cerium, terbium, as well as coactivated by the above ions, are studied. The selective interaction of some types of cerium and terbium centers is found. The effect on the central composition and the selective interaction of optically inactive of two- and four-valent additions as well as activator concentrations, is studied. It is shown that three of the four types of luminescence centers observed consist of rare earth ions and proper defects of the intermediate layer. It is established that proper defects of the LMHA structure distort a considerable range of crystal structure; the distortion envelops at least 2 constants of the lattice a and disturbs the energy of luminescence center structure and 12 (defect-vacancy of 2b cation) or 18 (2d vacancy) surrounding defect positions for a rare earth ion